Pent-up UK demand for the new iPhone 4S meant that Apple sold more than three times as many phones in October as in any of the three previous months, eclipsing the rival Google platform, according to data from Kantar Worldpanel ComTech.

Data released by the research company show Apple's iPhone took 42.8% of UK smartphone sales in October alone, ahead of all Android phones, which took 35% in the same period. The figures from ComTech also show the UK market is shifting dramatically towards smartphones: sales of smartphones grew by 43% in October, but the overall phone market dropped by 4% in October as "feature phone" sales nearly halved.

Smartphones made up 69.8% of sales over the three months, meaning 44.8% of the British population now owns a smartphone. But it also leaves 29 million adults in the UK not yet using a smartphone – representing a huge opportunity for rival brands.

The research company says the October boost meant that for the 12 weeks to the end of October, Apple's market share of UK smartphone sales was 27.8%, compared to 25% in the same period a year before. The Android platform continued to increase its overall lead, powering 46% of smartphones in the 12-week period, compared to 34.2% a year ago.

The Guardian's calculations suggest that Apple's sales jumped nearly fourfold in October as the iPhone 4S was released. Tim Cook, Apple's chief executive, complained that ahead of the launch, sales had slowed down substantially as people waited for the expected launch of the new iPhone – which many expected to be called the "iPhone 5". For those three months, ComTech's figures showed the iPhone's share of sales dropping to just 18.5%. Android phones made up 49%.

Despite looking the same as the iPhone 4, which was released in summer 2010, the iPhone 4S has clearly boosted Apple's fortunes in the UK. Dominic Sunnebo, global insight director at ComTech, noted that 75% of sales of iPhones in the period went to people who already owned one – indicating strong brand loyalty among existing customers, but equally that Apple may not be growing its market as quickly as it might want, as the overall smartphone market grew faster than that 25%.

The rapid expansion of Android sales suggests it is reaching new users who have not previously used the platform or even a smartphone.

Other data from ComTech showed that for the three-month period, Nokia's now-deprecated Symbian OS made just 3.9% of sales, down by 10.2%, and the Windows Mobile platform – officially all but discontinued – almost vanished, making just 0.5% of sales. BlackBerry maker RIM also saw its share fall, to 19.6% from 20.9%.

Microsoft's new Windows Phone platform saw a small uptick in sales, to 1% of the market from 0.2% a year ago, when it had just been launched. The ComTech figures predate the launch of Nokia's Lumia range, which are expected to boost Windows Phone's share noticeably.

Sunnebo said: "The October launch of the hugely anticipated iPhone 4S has catapulted Apple into second place among operating systems based on the last 12 weeks of sales. However, if you just look at the month of October, Apple took a whopping share of all smartphone sales, giving it a significant lead over Android – a feat many thought was impossible.

"With nearly a year and a half between iPhone launches there has been huge pent-up demand for a new Apple device. We have previously seen that Apple customers tend to be very loyal to the brand. However, it is still astonishing that 75% of new iPhone 4S owners previously owned an iPhone. Most of these loyalists tended to own previous generation devices such as the 3G or 3GS models. However, 14% previously owned an iPhone 4, demonstrating that quite a few people bought themselves out of their contracts to get hold of the 4S. Clearly the upgraded processor, camera and unveiling of Siri assistant was enough to generate excitement among the Apple community."

Sunnebo continues: "While unwavering loyalty is clearly great news for Apple, it is likely to be a relief for other smartphone operators. With Apple predominantly driving sales from within its existing customer base, it leaves the field wide open for the likes of Nokia, BlackBerry, Samsung and HTC to focus on converting the remaining 29 million adults who don't yet have a smartphone to their brand."